What are the best ways to get Call Backs from my Voicemails?

What are your tips when leaving voicemails? What’s the best way to get callbacks from voicemails when cold calling?

I'm a big fan of scripts! I was giving some very stuttery and hesitant sounding voicemails in my first few weeks in sales. My manager caught wind of it and recommended I make a few scripts. After that, it was just plug and play! After a while, I got pretty confident in how I sound in voicemails and the script kind of got memorized, so I don't need them anymore. But they were a great foundation for me!
I make sure to leave more than one voicemail if I can't connect with them. I'll make my first call and leave a voicemail. The next day, I'll do the same thing but I'll make sure that the voicemail is slightly different: it's either re-worded or has extra info to draw them in. My last voicemail is the same as the previous: re-worded, or even more info/reason why to call back. But each time I do this, I make sure to reach out to them through different channels! You can always trust they're checking their texts and emails. Leaving more than one voicemail and CTEing increase your chances to connect!
Both above are actually pretty accurate for me. My manager told me use scripts when I first started out. When the customer doesn't pick up, I'd rely on the script as my taling piece. Mostly to sound comfortable and for efficiency. After that, I send them a follow-up email. I was pretty surprised about how often people got back to me via email.